Time switch



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Feb. 15, 1955 Filed Oct. 30, 1952 F. w. TRUESDELL' Tm: swrrcn F/ga.

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United States Patent O" TIME SWITCH Francis W. Truesdell, West Lynn, Mass., assignor to General Electric Company, a corporation of New York Application October 30, 1952, Serial No. 317,691

24 Claims. (Cl. 20038) My invention relates to improvements in time switches, and in particular to an improved time switch especially useful for the control of electric range ovens and the like.

Time switches, or timers heretofore generally used for the control of electric range ovens have the disadvantage that the housewife, when setting the timer, must perform a manual switch-cocking operation, ll1 addition to setting the desired on" and ofi times for the oven. If, through inadvertence, the cocking operation is omitted, the timer will not operate properly, and the meal will not be cooked as planned.

Another common cause of improper operation in prior art range timers is that the hours to cook" interval may sometimes be set improperly for a longer period than the time remaining to the off or finish cooking" setting; and, in consequence, it may happen that the cooking cycle does not start until almost 12 hours later than was intended.

Another disadvantage of many prior art range timers is the complexity of switching means needed to change from timed control to manual control of the oven.

Principal objects of our invention are to abolish the aforementioned sources of inconvenience and frustration by providing an improved time switch which is automatically cocked when the cooking interval is set, which cannot be improperly set for a longer cooking interval than the time remaining to the finish cooking setting, which provides simple switching means for changing from timed control to manual control of the oven, or the reverse, and which nevertheless is relatively simple, highly reliable in operation, and economical to manufacture. Other objects and advantages will appear as the description proceeds.

Briefly stated, in accordance with one aspect of my invention, an axially movable pin is provided in telescoping alignment with a rotatable and axially movable shaft.

The desired switching operations are actuated by the respective axial motions of the pin and the shaft, as hereinafter explained. A rotatable tripping member, driven by a suitable clock or timing mechanism, releases the pin for axial motion when in predetermined angular relation to the shaft, and then drives the shaft to another predetermined angular position where it in turn is released for axial motion. The desired finish cooking and hours to cook settings are made by adjusting the initial relative angular positions of the shaft and the tripping member. Cooking is automatically effected by rotation of the parts while setting the desired cooking interval.

My invention will be better understood from the following description taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

In the drawings:

Fig. 1 is a front elevation of an improved range timer embodying principles of my invention,

Fig. 2 is similar to Fig. l, but with some of the parts removed or broken away,

Fig. 3 is a rear elevation of the same range timer,

Fig. 4 is a section taken generally along the line 4-4 of Fig. 2,

Fig. 5 is an exploded detail of a dial assembly shown in Fig. 4,

Fig. 6 is a plan view of a friction clutch member shown in Fig. 4,

Fig. 7 is an elevation of the clutch member shown in Fig. 6,

2,702,322 -Patentecl Feb. 15, 1955 Fig. 11 is a section taken generally along the line 11-11 of Fig. 2,

Fig. 12 is similar to Fig. 1, but with some of the parts removed or broken away, and some of the parts rotated,

Fig. 13 is a section taken 1313 of Fig. 12,

Fig. 14 is a detail taken generally along the line 14-14 of Fig. 13,

Fig. 15 is a detail showing the switch position for manual control of the oven,

Fig. 16 is a section taken generally along the line 16-16 of Fig. 3, and

Fig. 17 is a front elevation of another range timer adapted to control simultaneously two electric ovens.

Referring now to Figs. 1 and 2 of the drawings, the timer may be mounted in any suitable manner, preferably upon the backsplash 1 of the electric range. It may include clock means for indicating the time of day, which as illustrated comprises a numbered clock bezel 2, a minute hand 3, and an hour hand 4. Preferably, the hour hand 4 is painted upon the face of a rotatable disk 5 which is rotated by conventional clock mechanism at a rate of one revolution each 12 hours. If desired, the clock face may be protected by a glass cover in the conventional manner. For setting the clock, there may be provided a knob 6 which extends through the glass cover, attached to a shaft which carries minute hand 3. The clock may be set by turning knob 6 in the conventional manner.

The disk 5 is provided with an aperture 7 through which may be seen a portion of a rotatable dial 8. Dial 8 is coaxial with disk 5, and these two parts are rotated together by the clock mechanism. However, the dial 8 may be rotated independently of disk 5, as hereinafter more fully explained, by setting means including a knob 9. As knob 9 is turned, the angular relation between dial 8 and disk 5 is adjusted to any desired setting, and different portions of dial 8 become visible through aperture 7. Preferably dial 8 is numbered from 1 to 12 as shown, and any of these numbers may be brought into view through aperture 7, selectively, by turning knob 9. The numbers seen through aperture 7 indicate the time of day at which the cooking cycle will be completed, and the oven turned off.

The backsplash 1, or other mounting for the timer, is provided with an aperture 10 through which there may be seen a portion of a second rotatable dial 11. Preferably, dial 11 is numbered from zero to 6, and also carries the notations Off and Man, as shown. Any of these numbers or notations may be brought into view through aperture 10, selectively, by turning a setting knob 12. The number seen through aperture 10 indicates the duration of the cooking operation, i. e., the number of hours that the oven is to remain on.

For example, assume that the time of day is 12 o'clock, and that the housewife desires to cook food in the oven for a period of two hours, and have the cooking completed at 4 o'clock. To set the timer for this operation, she turns knob 9 until the numeral 4 is visible through aperture 7, and turns knob 12 until the numeral 2 is visible through aperture 10. The oven will remain off until 2 hours before 4 oclock, or 2 oclock, when the timer will operate to turn the oven on as hereinafter explained. Since dial 8 and disk 5 are rotated together by the clock mechanism, the numeral 4 remains visible through aperture 7, thus continuously indicating the finish cooking" time. Dial 11 remains stationary until the oven is turned on at 2 o'clock. Thereafter, dial 11 is also rotated by the clock mechanism, as hereinafter explained, so that the number visible through aperture 10 continuously indicates the amount of cooking time remaining to complete the cooking cycle. At 4 oclock, dial 11 will have been rotated to the position in which the numeral zero is visible through aperture 10. Dial 11 then moves suddenly to the position in which the nogenerally along the line tation Oil is visible through aperture 10, and the oven is turned off.

An important advantage of my improved timer is that the dial 11 cannot be set improperly for a longer cooking interval than the time remaining to the finish cooking setting. For example, assume again that the time is 12 oclock, and that the finish cooking time has been set for 4 o'clock. Knob 12 may be turned to bring into view through aperture 10 any of the numerals on dial 11 from zero to 4, selectively, but dial 11 cannot be turned beyond the numeral 4. Thus, proper setting of the timer is made very simple and straightforward, and the possibility of improper setting is minimized.

If it is desired to control the oven by manual controls only, without using the timer, knob 12 is turned until the notation Man" on dial 11 is visible through aperture 10. This closes the timer switch contacts, as hereinafter explained, and thus removes the timer from the circuit, so that the ovenis subject to the manual controls only. Thus, the manual switching is quite simple, and in fact semi-automatic, since setting the timer for a time-controlled cooking operation automatically connects the timer in the circuit, and only one simple operation is required to disconnect the timer and return the oven to manual control when desired. If desired, to further minimize the-possibility of incorrect settings, the portion of dial 11 around the notation Man may be painted a different color from the rest of the dial; for example, this portion may be painted white, while the remainder of the dial is painted red. Thus, the color seen through aperture 10 is white when the oven is under manual control only, and is red when the oven is under control of the timer. Additionally, there may be provided a pilot light 13, located in any convenient place, which is lighted only when the oven is under control of the timer, as hereinafter explained, and (s extinguished when the oven is subject to the manual controls only.

Referring now to Figs. 2, 3 and 4, the clock mechanism may comprise a small, synchronous electric motor 14 vhich'operates through suitable gearing, as shown, to turn the gear 15 at a fixed speed of one revolution per hour. Gear 15 is rotatable about shaft 16, and is connected thereto by conventional friction clutch means 17. The minute hand 3 and the clock-setting knob 6 are connected to shaft 16, as shown. Thus, the synchronous motor14 rotates the minute hand 3 at a speed of one revolution per hour, in the conventional manner. The clock may be set by turning knob 6 with sufiicient force to cause friction clutch means 17 to slip, in the usual way. The disk 5, upon which hour hand 4 is painted, is attached to a shaft 17 which is geared'to shaft 16 through gear 18 and pinion 19, so that shaft 17, and hence disk 5, are rotated at a fixed speed of one revolution each 12 hours. Shafts 16 and 17 are rotatably supported by an arbor 20 staked to a supporting plate 21. it will be appreciated that this clock mechanism is largely conventional, and that other clock mechanisms, such as a spring-driven clock, may be employed without altering the principles of my invention.

Referring now to Figs. 2, 4 and '5, the dial 8 is mounted upon a dome-shaped gear 22 having projections 23 which extend through holes in dial 8 so that dial 8 and gear 22 are held in fixed angular relation. Gear 22 is connected to shaft 17 through friction clutch means comprising a clutch member 24, more clearly shown in Figs. 6 and 7, having a plurality of resilient fingers, as shown, which frictionally engage a clutch surface 25 placed between the clutch member and the underside of gear 22. Thus, as the time-indicating disk 5, and the shaft 17 are driven at a fixed speed of one revolution each 12 hours by the clock mechanism, gear 22 and disk 8 are rotated at the same speed by the friction clutch 24. However, gear 22 and disk 8 may be rotated independently of the clock mechanism in the following manner:

Setting knob 9 is attached to a shaft 26 which is connected to gear 22 through gears 27. When knob 9 is turned with sufiicient force to overcome the friction of clutch 24, gear 22 and dial 8 are rotated independently of the clutch mechanism, thus adjusting the angular relation of dial 8 and disk to obtain the desired finish cooking setting. Disk 8 and gear 22 are held in place upon shaft 17 by a clip 28, more clearly shown in Fig.

4 8, which fits into a slot in shaft 17 as shown. Clip 28 also has an inwardly extending finger 29 which passes through a hole 30 in shaft 17 to engage a groove 31 in arbor 20, to hold shaft 17 in place on the arbor.

Referring now to Figs. 9 and 10 of the drawing, gear 22 engages a rotatable tripping gear 32 having an eat 33 extending from one of its sides as shown. As gear 22 rotates, it rotates gear 32 to maintain at all times a fixed angular relation between gear 32 and dial 8. For convenience, the direction in which the parts are rotated by the clock mechanism will be referred to herein as the forward direction and the opposite direction of rotation will be referred to as the reverse direction. It will be noted that the forward direction of rotation for gear 22 is clockwise, while the forward direction of rotation for gear 32 is counterclockwise.

Coaxial with gear 32 is a rotatable and axially movable shaft 34, having an axial bore 35 and a diametrical slot 36 extending transversely to the inner portion of bore 35. A lug 37 is attached to shaft 34 by a nut 38 and is held in fixed angular relation to the shaft by a key 39. Lug 37 cooperates with a plate 40 having an arcuate opening 41 which lug 37 may enter at certain angular positions of shaft 34, as hereinafter explained.

An outwardly extending arm 42, attached to shaft 34, carries a pivot 43 which is parallel to and rotates with the shaft. A latching lever 44, rotatably supported by pivot 43, extends generally outward from shaft 34 and rotates with the shaft. A slight clockwise rotation of lever 44 about pivot 43 forces the inner end of lever 44 into slot 36, while a slight counterclockwise rotation of lever 44 about pivot 43 withdraws the inner end of the lever at least partially out of the slot 36, for purposes hereinafter explained.

The dial 11 and the setting knob 12 (shown in Fig. ll) are attached to a shaft 45 positioned in axial alignment with shaft 34. Also attached to shaft 45 is a dog 46 which engages the outer portion of lever 44, so that clockwise rotation of shaft 45 causes dog 46 to press against the outer portion of lever 44, thus forcing the inner portion of lever 44 into slot 36 and thereafter producing clockwise rotation of shaft 34. An extension 47 of pivot 43 passes into a small, generally arcuate opening 48 of dog 46, so that shafts 34 and 45 rotate substantially together, but with sufiicient backlash provided by movement of extension 47 in slot 48 to permit the slight rotation of lever 44 about pivot 43 necessary to permit the inner end of lever 44 to move in or partially out of slot 36 selectively, as hereinafter explained. A spiral spring 49 may connect dog 46 with lever 44 as shown, so that the spring tends to press dog 46 lightly against the outer portion of lever 44, thus biasing the inner end of lever 44 to a position fully within slot 36.

A pin 50 is axially slidable within bore 35 and in telescoping axial alignment with shaft 34. When the inner end of lever 44 is fully within slot 36, lever 44 interferes with axial motion of pin 50 in relation to shaft 34 as hereinafter explained. This will be referred to as the latching position" of lever 44, since pin 50 is latched against axial motion. When the lower end of motion of pin 50 as hereinafter explained.

Assume now that the parts are in the position shown in Figs. 9 and 11, which is the Off position of the time switch. Gear 32 is rotated in a forward direction, coun- I terclockwise, at a fixed speed by the clock mechanism, as hereinbefore explained. As gear 32 rotates, note that dog 33 can pass under lever 44, so that none of the parts associated with shaft 34 interfere with rotation of gear 32. This will be referred to as the non-interfering position of shaft 34. Thus, when the time switch is in the Off position, there is minimum loading of the clock mechanism by the switch structure.

Now, assume that knob 12 is rotated clockwise to bring the parts into the position shown in Figs. 12, 13 and 14. As knob 12 is rotated, dog 46 presses against the outer portion of lever 44, thus forcing the inner end of lever 44 firmly into slot 36. Further rotation of knob 12 rotates shaft 34. As shaft 34 is rotated, lug 37 is forced out of arcuate opening 41, thus forcing shaft 34 to move axially backward. Lug 37 and plate 40 prevent shaft 34 moving axially forward until lug 37 is returned to its initial angular position, as hereinafter explained. The inner end of lever 44, being fully within slot 36, engages the shoulder at the forward end of pin 50, thus latching pin 50 against axial motion relative to shaft 34. Consequently, as shaft 34 is forced axially backward, pin 50 must move backward with the shaft.

Now as gear 32 rotates, ear 33 must eventually strike the outer portion of lever 44. Since there is now interference between ear 33 and lever 44, this axial position of shaft 34 will be referred to as the interfering position. After ear 33 reaches lever 44, further rotation of the gear 32 causes ear 33 to press against the outer portion of lever 44 and thus rotate lever 44 slightly counterclockwise about pivot 43. This withdraws the inner end of lever 44 at least partially from slot 36, thereby unlatching or freeing pin 50 for axial motion, so that pin 50 may move forward as far as is permitted by the interaction of yoke 51 and plate 40. As is hereinafter explained, this forward motion of pin 50 closes the switch contacts to turn the oven on.

Since dog 46 permits only a slight rotation of lever 44 about pivot 43, further rotation of gear 32 carries lever 44, pivot 43, arm 42, and shaft 34 around in a counterclockwise direction. When shaft 34 reaches its initial, or zero, angular position, as shown in Figs. 9 and 11, lug 37 re-enters opening 41. This permits shaft 34 to move axially forward which, as explained hereinafter, opens the switch contacts to turn the oven off. As shaft 34 moves forward, further axial motion of pin 50 is prevented by the interaction of yoke 51 and plate 40, so that pin 50 is withdrawn from bore 35 a sufficient amount to permit the lower end of lever 44 to re-enter slot 36, thus positioning the parts for resetting whenever desired by turning knob 12.

It will be noted that the forward axial motion of shaft 34, which turns the oven off and terminates the cooking operation, always occurs at one predetermined angular position of shaft 34 and its associated parts, and hence always occurs at the same angular position of gear 32. Since gear 32 can be made to arrive at this angular position at any desired hour of the day by turning knob 9 to adjust the relative angular position of dial 8 and disk 5, as hereinbefore explained, the OE or finish cooking time can be adjusted to any desired hour, and this hour is always indicated by the numeral visible through aperture 7. The length of time that the oven is to remain on is determined by the angular 'setting of shaft 34 and the latching lever 44, and this position is indicated by the numeral of dial 11 which is visible through aperture 10. After dog 33 has pressed against lever 44, and thereby released pin 50 to turn the oven on, shaft 34, and hence dial 11, rotates with gear 32, so that the angular position of dial 11 always indicates the amount of cooking time remaining. As soon as dial 11 reaches the zero position, lug 37 reenters opening 41, and in doing so produces a slight additional rotation of shaft 34 and dial 11 which quickly turns dial 11 to the position in which the notation Off is visible through aperture 10.

Improper setting of dial 11 for a cooking interval longer than the period remaining to the finish cooking setting is prevented by the interference of lever 44 and car 33. For example, assume that the time of day is 3 oclock, and the finish-cooking setting is 6 oclock. Ear 33 will then be at an angular position 90 degrees clockwise from the finish-cooking position. Consequently, dial 11 may be rotated by any amount up to 90 degrees clockwise, which will bring the numeral 3 in position to be seen through aperture 10. Any greater clockwise rotation of dial 11 is prevented by the interference between lever 44 and ear 33.

An improper setting might still be obtained if it were possible to first set dial 11, then rotate gears 22 and 32 in the reverse direction. This is prevented by an antireversing pawl 52, shown in Figs. 2 and 4 of the drawings. Pawl 52 engages gear 22 as shown. Forward, or clockwise, rotation of gear 22 causes pawl 52 to move upward, so that the teeth of the gear pass under the pawl. However, any substantial rotation of gear 22 in the reverse, or counterclockwise, direction forces the pawl against the lower edge at opening 53. The pawl then can move no further, and being in engagement with the teeth of of gear 22, the pawl prevents any further reverse rotation of the gear.

An important feature which prevents inadvertently setting the timer improperly is the fact that the radius of rotation of dog 46 is greater than the radius of rotation of ear 33. For example, assume that knob 12 is turned clockwise until lever 44 strikes car 33. No amount of clockwise pressure on knob 12 will cause ear 33 to unlatch lever 44, since the torque applied by dog 46, which tends to force the inner end of lever 44 into slot 36, exceeds the torque applied by ear 33, which tends to force lever 44 out of the slot. However, as soon as knob 12 is released, the forward motion of car 33 unlatc-Laes lever 44 and permits pin 50 to move forward. This feature is important in the following circumstance:

Assume that the time of day is 3 o'clock, and that the finish cooking time is set for 6 oclock. Assume that the desired cooking interval is 2 hours. However, knob 12 is inadvertently turned for a cooking interval of 3 hours, whereupon lever 44 is brought against ear 33. Then the setting is corrected and knob 12 is turned counterclockwise until the correct setting of 2 /2 hours is visible through aperture 10. This correction is permissible, since with my improved switch the rotation of lever 44 into contact with car 33, without a substantial subsequent movement of car 33, does not unlatch lever 44 and therefore does not turn the oven on. Consequently, the oven remains off for /2 hour until it is turned on in accordance with the corrected setting.

As an index in the center of aperture, 10, there may be provided a wire 54 supported at its upper end by a bracket 55 and looped around a groove in shaft 45, as shown. This type of index is desirable in that it partially follows the axial movements of shaft 45, and hence minimizes parallax error.

Referring now to Figs. 3, 11 and 13, there are attached to an electrically non-conducting terminal strip 56 two sets of electrical connectors 57 and 58, and two sets of resiliently flexible metal leaves 59 and 60. Leaves 59 and 60 are attached at one end to the terminal strip and extend generally outward therefrom as shown; and are electrically connected to connectors 57 and 58 respectively. The free ends of leaves 59 and 60 are provided with electrical contacts 61 and 62 respectively, which are aligned for the selective opening or closing of an electrical circuit between the two sets of leaves.

An electrically insulating bar 63 is attached between leaves 59 and rides against the nut 38 at the end of the shaft 34, so that leaves 59 are actuated by axial movement of shaft 34that is, a backward axial motion of shaft 34 moves bar 63 and leaves 59 backward; and upon lug 37 entering opening 41, the resilience of leaves 59 forces shaft 34 axially forward. The free ends of resilient leaves 60 rest against yoke 51, so that they are similarly actuated by axial movement of pin 50.

The two sets of leaves 59 and 60 are usually connected in series circuit between the electric oven and the manual oven controls. The manual controls may be separate switches on the backsplash of the range, or may be associated with the oven thermostat. In the Off position of the switch, as shown in Fig. 11, both sets of leaves are in their most forward position, so that the electrical circuit between contacts 61 and 62 is open.

'When the timer is set for a time-controlled cooking operation, as hereinbefore explained, leaves 59 and 60 are both forced backward to the position illustrated in Fig. 13. Contacts 61 and 62 remain open. When lever 44 is unlatched, as previously explained, pin 50 is released for axial motion, and the resilience of leaves 60 forces the free ends of leaves 60, yoke 51, and pin 50 forward. This closes the electrical circuit between contacts 61 and 62, and turns the oven on. When lug 37 enters opening 41, as hereinbefore explained, shaft 34 is released for axial motion, and the resilience of leaves 59 forces bar 63 and shaft 34 forward. Yoke 51 prevents further forward motion of leaves 60, and consequently the electrical circuit between contacts 61 and 62is opened, thus turning the oven otf.

Referring now to Figs. 9, l0 and 15, a cam'64, attached to shaft 34, is arranged to press backward against bar 63, thus closing the electrical circuit between contacts 61 and 62, when shaft 34 is rotated in the forward, or counterclockwise, direction from the position shown in Fig. 9. D ur1ng such rotation, lug 37 remains within arcuate opening 41, so that no axial motion of shaft 34 occurs and lever 44 remains in non-interfering relation to ear 33. This counterclockwise rotation of shaft 34 places the Man notation on dial 11 in position to be seen through aperture 10, and effectively disconnects the timer from the circuit so that the oven is subject to the manual controls only.

To actuate the pilot light 13 shown in Fig. l, a lever 65 is mounted upon bar 63 in amanner best shown in Figs. 9, 11 and 15. Lever 65 has a finger 66 which extends through an opening in bar 63 into the path of cam 64, so that upon rotation of dial 11 to the Man position, cam 64 presses against finger 66 as shown in Fig.- 15, and thereby opens a switch 67 which is elec trically connected in series circuit with the pilot light 13. Since switch 67 is closed in all other positions of shaft 34, the pilot light is lighted whenever the oven is under control of the timer, and is extinguished only when the timer is in the Man position and the oven is under the sole control of the manual switches. 1

Fig. 16 shows the manner in which the connectors 57 and 58 and the leaves 59 and 60 are attached to the terminal board 56. It is essential that good electrical contact be maintained between the connectors and the leaves, as any appreciable resistance in this connection could cause an excessive heating which might damage the terminal strip or other parts of the switch. To accomplish this, rivets 68 each have an intermediate shoulder 69 and two heads70, as shown. The electrical connector and the leaf are firmly held together between the shoulders 69 and one of the heads of the rivet, while the terminal strip is held between the shoulder and the other head of the rivet. Thus, any tendency of the terminal strip'to give slightly will not effect the electrical connection between the connector 57 and the leaf 59. For added-rigidity of the connectors 57 and 58, an additional insulating strip 71 may be connected across the com nector ends, as shown. 4

Fig. 17 shows a modification useful for the simultaneous control of two ovens, as in a two-oven electric range. In this modification, the center portion 72 is substantially identical to the left-hand portion of the timer shown in Figs. 1 and 2. The gear 73 is driven in a forward direction at a fixed speed by clock mechanism, in the same way that gear 22 is driven. The setting knob 74, for adjusting the angular relation of gear 73 to the hour hand of the clock, is located below the clock dial to leave the space to the left of the clock dial free for other purposes. For the same reason, the clock motor may be rotated 90 degrees from the position shown in Fig. 3. cated to the left and the right respectively of the clock face, are each similar to the mechanism on the righthand side of the timer shown in Figs. 1 and 2. Each has a tripping gear, 77 and 78 respectively, in engagement with gear 73, and each has a setting knob, 79 and 80 respectively, for setting the cooking interval for the two ovens to be controlled. The tripping gears 77 and 78 are rotated in unison by the gear 73.

In a two-oven range, unit 75 maybe connected to control one of the oven units, while unit 76 is connected to control the other oven unit. Either or both of the ovens may be left under manual control, by turning the corresponding timer unit to the Man position. Alternatively, both ovens may be controlled simultaneously by the timer, in which event the cooking cycle will end simultaneously for both ovens at the time set by knob 74 and indicated by' the numeral visible through aper ture 81. However, the cooking intervals for the two ovens may be set independently by knobs 79 and 80, the respective intervals being indicated by the numerals visible through apertures 82 and 83. Thus, different foods having different cooking times may be placed in the two ovens, and when the timer is properly set, each will be cooked the desired length of time, and both will be ready to serve at the same time. Alternatively, one of the timer units may control the oven, and the other timer unit may control surface heaters of a single-oven range.

It will be understood that my invention is not limited to the specific embodiments herein illustrated and described, and that the following claims are intended to cover all changes and -modifications which do not de part from the true spirit and scope of the invention.

What I claim'as new and desire to secure by Letters Patent of the United States is:

1. A time switch comprising a rotatable tripping The timer mechanisms 75 and 76, lo-

member having an car on one of its sides, mechanism for rotating said tripping member at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, a member rotatable with said shaft and extending outward therefrom so that axial movement of the shaft positions said outwardly extending member selectively in interfering or non-interfering relation to said ear, and means for moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position, and moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position.

2. A time switch comprising a tripping gear having an ear extending upwardfrom one of its sides, mechanism for rotating 'asid gear at a fixed speed, a rotatable and axially movable shaft coaxial with said gear, a member rotatable with-said shaft and extending outward therefrom so that axial movement of the shaft positions said outwardly extending member selectively in interfering or non-interfering relation to said car, a fixed plate having an opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate, thereby moving said shaft axially to the non-interfering position, upon rotation of the shaft to a predetermined angular position and is forced out of the opening, thereby moving said shaft axially to the interfering position, upon' rotation of the shaft away from such angular position, and a switch member actuated by axial motion of said shaft.

3. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, clock mechanism including a time-indicating member which rotates at a fixed speed, a rotatable dial connected in fixed angular relation to said tripping member, friction clutch means connecting said dial in adjustable angular relation to said time-indicating member, whereby said dial and said tripping members are rotated in a forward direction at a fixed speed by said clock mechanism through said friction clutch, a rotatable and axially movable shaft coaxial with said tripping member, a member rotatable with said shaft and extending outward therefrom so that axial movement of the shaft positions said outwardly extending member selectively in interfering or non-interfering relation to said ear, and means for moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position.

4. A time switch comprising a tripping member, timing mechanism for moving said tripping member, a member having a bore and having a slot extending trans- 'versely into said bore, a pin axially slidable within said bore, a pivot, and a latching lever rotatably supported upon said pivot, one end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, a portion of said lever interfering with a por-- tion of said tripping member, whereby motion of said tripping member brings a portion thereof against said lever and withdraws the lever from said slot to release said pin for axial motion.

5. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member at a fixed speed, an axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescop ing axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever interfering with motion of said ear, whereby rotation of said tripping member brings the ear aaginst the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, and a switch member actuated by axial motion of said pin.

6. A time switch comprising a rotatable trippin member, mechanism including a timing member whic rotates at a fixed speed, a rotatable dial connected in fixed angular relation to said tripping member, clutch means connecting said dial in adjustable angular relation to said timing member, a shaft having an axial bore and also having a diametrical slot extending into said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with said shaft, and a latching lever rotatably supported upon said pivot and extending outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, a portion of said lever interfering with a portion of said tripping member, whereby rotation of said tripping member brings a portion thereof against said lever and withdraws the lever from said slot to release said pin for axial motion.

7. A time switch comprising a gear having an ear extending from one of its sides, mechanism for rotating said gear at a fixed speed, a rotatable and axially movable shaft coaxial with said gear, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable, selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position, rotation of said gear brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, means for moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position, means restricting axial motion of said pin whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufficiently to permit the inner end of said latching lever to re-ent er said slot, and a switch member actuated by axial motion of said pin.

8. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position, rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the noninterfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening, thereby moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufficiently to permit the inner end of said latching lever to re-enter said slot, a first switch member actuated by axial motion of said shaft, and a second switch member actuated by axial motion of said pin.

9. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable shaft coaxial with said tripping member, a pivot parallel with and; attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, said lever being rotatably to a latching position or an unlatching position selectively, an outer portion of said lever interfering with motion of said ear, whereby rotation of said tripping member in the forward direction brings the ear against the outer portion of the latching lever, thereby rotating said lever to the unlatching position, switch means actuated by rotation of said lever to the unlatching position, a rotatable set ting member in axial alignment with said shaft, an outwardly extending dog attached to said setting member, the outer portion of said dog interfering with said latching lever whereby rotation in the reverse direction of said setting member relative to said shaft rotates said lever to the latchingposition, said dog having a greater radius of rotation than said ear, and connecting means for rotating said shaft in substantial correspondence with rotation of said setting member, said connecting means having backlash to permit sufficient relative motion between said setting member and said shaft for the latching and unlatching rotation of said lever.

10. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable shaft coaxial with said tripping member, an outwardly extending arm attached to said shaft, a pivot attached to said arm and parallel with said shaft, a latching lever rotatably supported upon said pivot and extending generally outwardly from said shaft, said lever being rotatable to a latching position or an unlatching postion selectively, an outer portion of said lever interfering with motion of said ear, whereby rotation of said tripping member in the forward direction brings the ear against the outer portion of the latching lever, thereby rotating said lever to the unlatching position, switch means actuated by rotation of said lever to the unlatching position, a rotatable setting knob in axial alignment with said shaft, an outwardly extending dog attached'to said setting knob, the outer portion of said dog interfering with said latching lever, whereby rotation in the reverse direction of said setting knob relative to said shaft rotates said lever to the latching position, said dog having a greater radius of rotation than said ear, said dog having a substantially arcuate cutout portion, said pivot having an extension passing into said cutout portion for rotating said shaft in substantial correspondence with rotation of said setting knob and providing backlash to permit sutficient relative rotation between said setting knob and said shaft for the latching and unlatching rotation of said lever, and a spring connected between said lever and said dog tending to rotate the dog against said latching lever.

11. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever interfering with motion of said ear, whereby rotation of said tripping member in the forward direction brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a switch member actuated by axial motion of said pin, a rotatable setting member in axial alignment with said shaft, an outwardly extending dog attached to said setting member, the outer portion of said dog interfering with said latching lever, whereby rotation in the reverse direction of said setting member relative to said shaft rotates said lever to the latching position, said dog having a greater radius of rotation than said ear, and connecting means for rotating said shaft in substantial correspondence with rotation of said setting member, said connecting means having backlash to permit sutficient relative motion between said setting 1 member and said shaft for the latching and unlatching rotation of said lever.

12. A time switch Comprising a tripping gear having an ear extending from one of its sides,\ mechan1sm for rotating said gear in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said gear, said shaft having an axial bore and also having a diarnetrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, an outwardly extending arm attached to said shaft, a pivot attached to said arm and parallel with said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively to a latching position in or an unlatching position substantially out of said slot and interferring when in the slot with the axial motion of said pin, an outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when the shaft is in the interfering position, rotation of said gear brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said s lot to releas e said pin for axial motion, means for moving sa1d shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position, means restricting axial motion of said, pin whereby axial motion of said shaft to the non-interfering position Withdraws said pin from said bore sufficiently to permit the inner end of said latching lever to re-enter said slot, a switch member actuated by axial motion of said pin, a rotatable setting knob in axial alignmentwith said shaft, an outwardly extending dog attached to said setting knob, the outer portion of said dog interfering with said latching lever, whereby rotation in the reverse direction of said setting knob relative to said shaft rotates said lever to the latching position, said dog having a greater radius of rotation than said ear, said dog having a substantially arcuate cutout portion, said pivot having an extension passing into said cutout portion for rotating said shaft in substantial correspondence with rotation of said setting knob and providing backlash to permit sufiicient relative rotation between said setting knob and said shaft for the latching and unlatching rotation of said lever, and a spring connected between said arm and said dog tending to rotate the dog against said latching lever.

13. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping-member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axialty slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inher end of said lever being movable selectivelyto a latching position in or an unlatching position substantially out of said slot and interfering when in the slot with the axial motion of said pin, an outer portion of said lever being sitioned by axial movement of said shaft selectively in mterferring or non-interfering relation to said ear, whereby when said shaft is in the interfering position, rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufficiently to permit the inner end of said latching lever to re-enter said slot, at first switch member actuated by axial motion of said shaft, a second switch member acuated by axial motion of said pin, a rotatable lettingmember in axial alignment with said shaft, an outwardly extending dog attached to said setting member, the outer portion of said dog interfering with said latching lever, whereby rotation in the reverse direction of said setting member relative to said shaft rotates and lever to the latching position, said dog having a greater radius of rotation than said ear, and connecting means for rotating said shaft -in substantial correspondence with rotation of said setting member, said connecting means having backlash to permit sufiicient relative motion between said setting member and said shaft for the latching and having an opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position, and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular position, a switch member actuated by axial motion of said shaft, and a cam attached to said shaft and arranged to actuate said switch member upon rotation of the shaft in the forward direction, said lug remaining within the opening in said plate during such forward rotation.

15. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, clock mechanism including a time indicating member which rotates in a forward direction at a fixed speed, a rotatable.

dial connected in fixed angular relation to said tripping member, friction clutch means connecting said dial in adjustable angular relation to said time-indicating member, a rotatable and axially movable shaft coaxial with said tripping member, a member rotatable with said shaft and extending generally outward therefrom so that axial movement of the shaft positions said outwardly extending member selectively in interfering or non-interfering relation to said ear, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular position, a switch member actuated by axial motion of said shaft, and a cam attached to said shaft and arranged to actuate said switch member upon rotation of the shaft in the forward direction, said lug remaining within the arcuate opening in said plate during said forward rotation.

16. A time switch comprising a rotatable tripping memher having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shafta latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate, thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position. and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular posltion, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said boretsutliciently to permit the inner end of said latching lever to re-enter said slot, a first switch member'actuated by axial motion of said shaft, a second switch member actuated by axial motion of said pin, and a cam attached to said shaft and arranged to actuate said first switch member upon rotat on of the shaft in the forward direction, said lug remaining within the arcuate opening in said plate during sa1d forward rotation.

17. A time switch comprising a rotatable tr1pping member having anear extending from one of liS sldes, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said trlpping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of sa d bore, a p1n axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from sa1d shaft, the inner end of said lever being movable selectively to a latching position in or an unlatch ng posttlon substantially out of said slot and interfering when m the slot with the axial motion of said pin, an outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position, rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that sa1d lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the mterfering position upon rotation of the shaft 1n the reverse direction away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufiiciently to permit the inner end of said latching lever to re-enter said slot, a first switch member actuated by axial motion of said shaft, a second switch member actuated by axial motion of said pin, a cam attached to said shaft and arranged to actuate said first switch member upon rotation of the shaft in the forward direction, said lug remaining within the arcuate opening in said plate during such forward rotat on, a rotatable setting member in axial alignment with said shaft, an outwardly extending dog attached to said setting member, the outer portion of said dog inter fering with said latching lever, whereby rotation in the reverse direction of said setting member relative to said shaft rotates said lever to thelatching position, said dog having a greater radius of rotation than said ear, and connecting means for rotating said shaft in substantial correspondence with rotation of said setting member, said connecting means having backlash to permit sufficient relative motion between said setting member and said shaft for the latching and unlatching rotation of said lever.

18. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, a member rotatable with said shaft and extending generally outward therefrom so that axial movement of the shaft positions said outwardly extending member selectively in interfering or non-interfering relation to said car, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening, thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular position, a first switch member actuated by axial motion of said shaft, a cam attached to said shaft and arranged to actuate said first switch member upon rotation of shaft in the forward direction, said lug remaining within the arcuate opening in said plate during such forward rotation, and an additional switch member actuated only by rotation of said cam in the forward direction.

19. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or noninterfering relation to said ear, whereby when said shaft is in the interfering position rotation of said. tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of I said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate, thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufficiently to permit the inner end of said latching lever to re-enter said slot, 9. first switch member actuated by axial motion of said shaft, a second switch member actuated by axial motion of said pin, a cam attached to said shaft and arranged to press against and actuate said first switch member upon rotation of the shaft in the forward direction, said lug remaining within the arcuate opening in said plate during such forward rotation, and a third switch member arranged for actuation by being moved relative to said first switch member by the rotation of said cam in the forward direction.

20. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outwardly from saidshaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in the interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufficiently to permit the inner end of said latching lever to re-enter said slot, a terminal strip, first and second sets of'resiliently flexible leaves each attached at one end to said terminal strip and extending outward therefrom, the free ends of said leaves having electrical contacts aligned so that motion of one set of leaves relative to the other selectively opens or closes electrical circuits therebetween, and an insulating bar attached to said first set of leaves and riding against the end of said shaft, whereby axial motion of said shaft moves the slot extending to the inner portion of said bore, a pm' axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position, rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of the shaft to the noninterfering position withdraws said pin from said bore sutficiently to permit the inner end of said latching lever to re-enter said slot, a terminal strip, first and second sets of resiliently flexible leaves each attached at one end to said terminal strip and extending outward therefrom, outer portions of said leaves having electrical contacts-aligned so that motion of one set of leaves relative to the other selectively opens or closes electrical circuits therebetween, an insulating bar attached to said first set of leaves and riding against the end of said shaft whereby axial motion of said shaft moves the outer portion of said first set of leaves, the outer portion of said second set of leaves resting against said yoke and thereby being moved by axial motion of said pin, and a cam attached to said shaft and arranged to push said bar away from the end of said shaft upon rotation of the shaft in the forward direction, said lug remaining within the arcuate opening in said plate during such forward rotation, thereby moving said first set of leaves relative to said second set.

22. A time switch comprising a rotatable tripping member having an ear extending from one of its sides, mechanism for rotating said tripping member in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping member, said shaft having an axial bore and also having a diametrical slot extending to the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, a pivot parallel with and attached to said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively in or substantially out of said slot and interfering when in the slot with the axial motion of said pin, the outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position rotation of said tripping member brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon'rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfermg position upon rotation of the shaft in the reverse direction away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufiiciently to permit the inner end of said latching lever to re-enter said slot, a terminal strip, first and second sets of resiliently flexible leaves each attached at one end to said terminal strip and extending outward therefrom, outer portions of said leaves having electrical contacts aligned so that motion of one set of leaves relative to the other selectively opens or closes electrical circuits therebetween, an insulating bar attached to said first set of leaves and riding against the end of said shaft, whereby axial motion of said shaft -moves the outer'portion of said first set of leaves, the

outer portion of said second set of leaves resting against said yoke and thereby being moved by axial motion of said pin, a cam attached to said shaft and arranged to push said insulating bar away from the end of said shaft upon rotation of the shaft in the forward direction, said lug remaining within the arcuate opening in said plate during such forward rotation, thereby moving said first set of leaves relative to said second set, said insulating bar having an opening, and switch means including a lever mounted upon said bar and having a finger extending through said opening in the bar into the path of said cam so that rotation of said cam in the forward direction moves said lever relative to said bar.

23. A time switch comprising an electrically non-conducting terminal strip, a plurality of resiliently flexible switching leaves extending outward from said terminal strip, a plurality of electrical connectors, a plurality of rivets connecting respective ones of said connectors to said leaves and attaching said leaves and connectors to said terminal strip, said rivets each having an intermediate shoulder and two heads, the connector and leaf being held together between the shoulder and one head of the rivet and the terminal strip being held between the shoulder and the other head of the rivet, and means for moving said switching leaves selectively to circuit-opening or circuit-closing position.

24. A time switch comprising a rotatable tripping gear having an ear extending from one of its sides, clock mechanism including a time-indicating member for rotating said tripping gear in a forward direction at a fixed speed, a rotatable and axially movable shaft coaxial with said tripping gear, said shaft having an axial bore and also having a diametrically slot extending to'the inner portion of said bore, a pin axially slidable within said bore in telescoping axial alignment with said shaft, an outwardly extending arm attached to said shaft, a pivot attached to said arm and parallel with said shaft, a latching lever rotatably supported upon said pivot and extending generally outward from said shaft, the inner end of said lever being movable selectively to a latching position in said slot or an unlatching position substantially out of said slot and interfering when in the slot with the axial motion of said pin, an outer portion of said lever being positioned by axial movement of said shaft selectively in interfering or non-interfering relation to said ear, whereby when said shaft is in the interfering position, rotation of said tripping gear brings the ear against the outer portion of the latching lever, thereby withdrawing the inner end of said lever from said slot to release said pin for axial motion, a plate having an arcuate opening therein, a lug attached to said shaft and cooperating with said plate so that said lug enters the opening in the plate thereby moving said shaft axially to the non-interfering position upon rotation of the shaft to a predetermined angular position and is forced out of the opening thereby moving said shaft axially to the interfering position upon rotation of the shaft in the reverse direction away from such angular position, a yoke attached to said pin and cooperating with said plate to restrict the axial motion of said pin, whereby axial motion of said shaft to the non-interfering position withdraws said pin from said bore sufficiently to permlt the inner end of said latching lever to re-enter said slot, an electrically non-conducting terminal strip, first and second sets of resiliently flexible switching leaves extending outward from said terminal strip, outer portions of said leaves having electrical contacts aligned so that motion of one set of leaves relative to the other selectively opens or closes electrical circuits therebetween, a plurality of electrical connectors, a plurality of rivets connecting respective ones of said connectors to said leaves and attaching said leaves to said terminal strip, said rivets each having an intermediate shoulder and two heads, the connector and leaf being held together between the shoulder and one head of the rivet and the terminal strip being held between the shoulder and the other head of the rivet, an insulating bar attached to said first set of leaves and riding against the end of said shaft, whereby axial motion of said shaft moves the outer portion of said first set of leaves, the outer portion of said second set of leaves resting against said yoke and thereby being moved by axial motion of said pin, a cam attached to said shaft and arranged to push said bar away from the end of said shaft upon rotation of the shaft in the forward'direction, said lug remaining within the arcuate opening in said plate during such forward rotation, thereby moving said first set of leaves relative to said second set, said bar hav- 5 ing an opening, switch means including a lever mounted upon said bar and having a finger extending through said opening in the bar into the path of said cam, so that rotation of said cam in the forward direction moves said lever relative to said bar, a rotatable setting knob in .axial alignment with said shaft, a dial attached to said setting knob, an outwardly extending dog attached to said setting knob, the outer portion 'of said dog interfering with said latching lever, whereby rotation in the reverse direction of said setting knob relative to said shaft rotates said lever to the latching position, said dog having a greater radius of rotation than said ear, said dog having an arcuate cutout portion, said pivot having an extension passing into said cutout portion for rotating said shaft in substantial correspondence with rotation of said setting knob and providing backlash to permit sufficient relative motion between said setting knob and said shaft for the latching and unlatching rotation of said lever, and a spiral spring connected between said arm and said lever tending to rotate the lever to the latching position.

References Cited in the file of this patent UNITED STATES PATENTS 2,499,270 Ellis Feb. 28, 1950 

